Howard writes from Agawam, Massachusetts: "I started finishing a bonus room over my garage and want to insulate it the best I can. The room is framed with box trusses 24"oc, the knee walls are only 2" x 4", and the slanted portion between the knee wall and the ceiling has 2" x 6" that I already built out with 2" x 3" for a total cavity depth of 7-7/8". In the slanted portion I was planning to use R 22 6-3/4" kraft faced pink batts which would leave 1-1/8" air space for roof ventilation. I would staple the kraft facing to the interior side of the wall, and then plan to add Foamular rigid foam to the inside of the interior side studs to increase the R-value before attaching the dry wall. So the construction would be Sheet rock/Foamular/Kraft Faced Batts/1" air space/Roof sheathing. I have read conflicting information and want to know if this is a good idea to maximize R-value while not creating a moisture problem by putting the kraft facing up against the Foamular. What is your recommended insulation construction for my application?"

Answer: Good question. Actually, Owens Corning recommends using unfaced insulation in this system. Everything else matches the company's recommendation.